Forced air heating and air conditioning systems commonly include an air filter to remove particulates and other impurities from the circulating air. These air filters generally consist of a filter media (e.g., a fibrous mat or porous foam) that is held within a frame. The frame provides the air filter with mechanical strength and rigidity so as to facilitate mounting of the air filter in the air handling equipment. Frequently, these air filters must be replaced on a periodic basis. Alternatively, the air filters can be designed to be washable.
Unfortunately, the air filters that are commercially available for use in heating and air conditioning systems have a number of shortcomings. For example, the air filters have frames with a rigid rectangular shape to aid insertion into the heating and air conditioning equipment, typically by inserting the rectangular frame into opposed horizontal slots across an air duct. When a dirtied air filter frame is removed for disgarding, the rigid frame, the dirt and debris collected on the inlet air side of the filter can fall off the filter when placing the dirtied filter into a trash receptacle or trash bag.